How Often Do You Need to Change Your Toothbrush?

Your toothbrush is home to over 100 million germs. You can’t see them but they’re there, living and thriving. You transfer these germs from your toothbrush to your mouth every time you brush your teeth.

Thanks to your immune system, the bacteria on your toothbrush probably won’t make you sick. And it’s not a reason to stop brushing your teeth. But it is important to replace your toothbrush regularly.

Below, we’ll look at the signs of an overused toothbrush, how often you should replace your toothbrush, and tips for cleaning your toothbrush.

How often should I replace my toothbrush?

The American Dental Association (ADA) recommends replacing your toothbrush every 3 to 4 months.

There are two common types of toothbrushes on the market: manual and battery powered. They’re both equally effective at cleaning your teeth. But regardless of the type of brush you use, the bristles will fray after a few months. Worn-down bristles make brushes less effective at breaking down plaque and fighting gum disease.

For the best cleaning results, set a reminder to get a new brush or brush head every few months.

How to tell when it’s time to replace your toothbrush

There are other situations where you may want to replace your toothbrush before 3 to 4 months. Here are some things to look for:

• When the bristles look worn: If they’re bent or frayed, it’s time to get a new toothbrush. Bristles that no longer stand up straight aren’t as effective at removing food particles from your teeth and gums.

• When there’s buildup at the bottom: Debris and germs may settle at the bottom of your bristles. If you notice gunk and can’t remove it, throw it out and get a new one.

• After traveling: Many people store their toothbrushes in plastic containers when they travel. Unfortunately, bacteria thrive in moist, enclosed spaces like toothbrush holders. As soon as you get home, get rid of your old toothbrush.

• After contact with another toothbrush: You don’t want to cross-contaminate your toothbrush with someone else’s. If yours comes in contact with another person’s toothbrush, definitely trash it.

• When you can’t remember: If you can’t remember the last time you swapped out your toothbrush, it’s probably time to replace it.

Can an old toothbrush make you sick?

Your immune system can protect you from many harmful bacteria, including the millions of germs that live on your toothbrush. Many researchers agree that toothbrushes will probably not make you sick.

But research on this topic is ongoing and the results are mixed. A small 2020 study suggests that the bacteria on toothbrushes raises the risk for:

• Infections

• Heart disease

• Cancers

• Nervous system diseases

While the jury is still out, we can settle on the fact that millions of microorganisms live on your toothbrush. The best way to protect your health is to replace your toothbrush regularly rather than to use an old toothbrush.

Is it OK to use the same toothbrush after you’ve been sick?

You don’t need to replace your toothbrush when you have a cold or flu symptoms. The ADA says you probably won’t reinfect yourself. But, if you have a compromised immune system or if your toothbrush is 3 to 4 months old, go ahead and replace it once you feel better.

Tips for keeping your toothbrush clean

Even though the risk of getting sick from your toothbrush is low, you still want to keep it clean. These tips can help:

• Don’t share your toothbrush, not even with your partner or kids. You risk exchanging germs between you and the other person.

• Rinse your toothbrush with water when you’re done using it to remove excess toothpaste or food particles.

• When you’re not using it, place your toothbrush in an upright position so it can air dry.

• Don’t store your toothbrush in a closed container. The moisture and lack of air will promote germ growth.

• Keep your toothbrush separated from other toothbrushes to avoid contamination.

• Don’t microwave or run your toothbrush in the dishwasher. It can damage your brush.

• Keep your toothbrush as far away from the toilet as possible. When you flush a toilet, it releases a germy poop mist into the air that can settle on your toothbrush.

• If you’re interested in sanitizing your toothbrush, use 3% hydrogen peroxide or Listerine Antiseptic mouthwash. The Children’s Oral Health Institute recommends storing your brush in a mixture of 1 tsp peroxide with 1 cup of water overnight or soaking it in an antibacterial mouthwash for 30 seconds.

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Written by:

Ana Gascon

Ana Gascon has over 15 years of writing and editing experience, with 8 years in health and medical content work. She is a content creator who focuses on acute conditions, chronic diseases, mental health challenges, and health equity.

Edited by:

Renée Fabian, MA

Renée Fabian is the senior pet health editor at GoodRx. She’s worked for nearly 10 years as a journalist and editor across a wide range of health and well-being topics.

Reviewed by:

Patricia Pinto-Garcia, MD, MPH

Patricia Pinto-Garcia, MD, MPH, is a medical editor at GoodRx. She is a licensed, board-certified pediatrician with more than a decade of experience in academic medicine.

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